Office equipment utilizing a video display and keyboard input is known. The widespread use of these devices has proven that, in many cases, severe physical strain results from their daily use. Many attempts have been made to reduce the strain caused by these devices by positioning the keyboard, display screen, and other associated components appropriately. None of these solutions has been completely successful.
One company, PROFORMIX, offers a negative-slope keyboard support that is positioned below a desk top by an angled bracket. The keyboard support is part of an integrated workstation system including a copyholder, a mouse and a writing platform as part of an effort to improve overall body posture.
Traditional flat/rectangular keyboards typically taper from a low front elevation to a slightly higher rear elevation. In addition, these keyboards usually have an adjustable support which can further elevate the rear surface.
Depending upon the height of the desk that supports the keyboard, the hand-wrist junction of the user will either be in (a) a neutral position, or undesirably postured into either (b) a flexion position, or (c) an extension position.
The effect of the configuration of present-day keyboards is to force the hand-wrist junction into an undesirable extension posture to access the keyboard. A neutral hand-wrist posture is only possible if the keyboard platform is set at a much higher plane, i.e. at approximately thirty-six inches, as opposed to an average desk height of approximately twenty-five to twenty-seven inches. This extension posture of the hand-wrist junction is evident when the user chooses to access the keyboard with the wrist higher than the elbow.
In using a computer, the relation of vision to hand/finger actuated keyboard usage in performing fine motor-coordinated functions is influenced by the physical location, size, and collective placement of the keys. Traditional nonprehensile flat/rectangular keyboard applications usually require a high and nearly constant level of visual attention.
Workpace and related physiological changes, aging, onset of monocularization (intermittent lapsing of binocularity for near vision) that accompanies presbyopia, tool colors, and background contrast are factors affecting constancy of visual attention to task performance. Capitas extension, excessive excyclotorsion, and repetitive strain injuries (such as carpal tunnel syndrome) are common and debilitating concomitants to computer usage. These problems can be remedied by improved keyboard design.